Automatic slack-adjusting means for brakes.



f Patented Oct 29, l90l..

s. J. JpHNsoN. y AUTOMATIC SLACKvAD-IUSTING MEANS FOB BRAKES.

(No Model.)

(Application filed Aug. 29, 1900. Renewed Aug. 1, 1901.)

. MIIlIMIRIA k UNrTnn' STATES PATENT rriois.

s'INOLAIR J. JOHNSON, oF-NU'rLnY, Nnw JERSEY.

AUTOMATIC suACK-ADJUSTQING MEANSV FOR BRAKES SPECXFIOATION forming pareof Letters `Patent No. es5,3so, dated october 29, 1901. Applicationfiled August 29, 1900I Renewed August l, 1901. Serial No. '701499. (N0model.)

vT0 @ZZ whom t may concern:

Be it known that I, SINCLAIR J. JOHNSON, a citizen of the United States,residing in Nutley, in the' county of Essex and State of New Jersey,have invented certain new and useful Improvements in AutomaticSlack-Adjusting Means'for Brakes, of which the following is aspecication.

Y This invention relates to brakes, more particularly to an improvedslack-adjuster therefor,I the object of the invention being to provideimproved automatic means for taking up the slack thereof, thereby toenable the brake-shoes to effectively act upon the Wheels of the vehicleeach time the brakes are set.

A further object of the invention is to provide an improved automaticslack-adjuster for brakes so constructedthat it can be applied withoutmaterial change to the brake mechanism ordinarily used on railway-cars,the organization being such that'the nu mber of parts forming the sameare comparatively few and the assemblage and operation thereof simple.

In the drawings accompanying and forming part of this specification,Figure 1 is a longitudinal sectional viewof a brake-cylinder such asthat ordinarily used with the Westinghouse brake system with thisimproved slack-adjusting means for brakes connected therewith, theorganization shown being that usually used in connection withfreight-cars.v Fig. 2 is a longitudinal sectional vview substantiallysimilar to that shown in Fig. 1, the organization shown'beingthatusually used in connection with passenger-cars. Fig. 3 is a longitudinalsectional view of a somewhatdifferent form of the slaclr-adjusting meansshown in Figs. l and 2. Figs. and 5 are views of the actuator. Fig. 6 isa cross-sectional view taken in linea ct,"Fi'g. 1, of a device theoperation of which'is'controlled by the actuator. Fig. 7 comprisesaneccentrically-operative means which may be used in place of the deviceshown in Fig. 6. Fig. 8 is a detail view of the ratchet devices shown inFigs. 1, 2, 3, and 6; and Fig. 9 is a crosssectional vView taken inlineh b, Fig. 2.

Similar characters of reference designate corresponding parts throughoutthe several views.

InY the form shown this improved automatic with some brake systems..ference between the freight-car brake-cylinder and the passenger-carbrake-cylinder is 'that in the former the piston-rod 5 is usual-ly Aatubular member passing through one end slack-adjuster comprises meansadjustably connected with the lever mechanism of a brake system-such,for instance, as with a cross-head thereof-and which consists of apiston member comprising, when the brakecylinder is of that form usuallyused with freight-cars, a push bar or rod formingapart of or havingconnection with the tubular piston-rod, or comprising, when the form ofbrake-cylinder usually used with passengercars is provided, thepiston-rod itself, means for ,adjusting this piston member, whichpreferably comprises a rotary device, which will for the purposes of thedescription and claims be designated as a ratchet mechanism, althoughthe same may not necessarily be provided with ratchet-teeth, and anactuator or actuating means comprising in the form shown a cam member.Since, as hereiubefore stated, this improved automatic slack-take-upmeans for brakes is adapted for use with the ordinary brake-cylinder asused in connection with freight or passenger cars, therefore in Fig. 1 abrakecylinder A adapted for use with freight-cars is shown, While inFig. 2 is illustrated abrakevcylinder B for use with passenger-cars.Each of these brake-cylinders is provided with an air-inlet 2 adjacentto the piston 3, comprising the usual piston-head 4, connected with fitspiston-rod 5, the return of which piston to its normal position beingcontrolled by a spring 6, although other means may be used The essentialdifof the brake-cylinder and connected in some ysuitable manner, as bymeans of a sliding push rod or bar, with the cross-head of the levermechanism, while'in the passenger-car brake-cylinder the piston-.rod isusually a solid bar or rod likewise passing through one end of thebrake-cylinder and connected in some suitable manner with saidcross-head.

In the form shown herein and which may bc its preferred form, ifdesired, this improved slack-take-up means comprises an actuator 8,shown herein as a sleeve one end of which is formed to engage andpreferably encircle one end of the brake-cylinder, to which IOO it issecured in some suitable manner, as by screws or bolts 9. This actuatoris provided with a cam-path, shown as a pair of oppositely-located andindependently-acting surfaces 10, formed by cutting away a portion ofsaid sleeve to form an opening, the side faces d and b of which arestraight, while the end faces c and d thereof are curved in accordancewith the path which the device operated by said actuator is to follow.In the form shown these curved surfaces are of substantially spiralformation. From the above it will be seen that this actuator is in thenature of a cam member or actuator. In the present instance thecross-head is provided with a tubular interiorly-threaded member 12,projecting into the actuator-sleeve 8.

In the form illustrated in Fig. 1 the crosshead is connected by means ofits threads to a piston member 13, shown in this instance as a push-bar,which preferably has an enlarged threaded end llt, which through themeans about to be described is. rotated within the tubular portion ofthe cross-head member 7 to thereby shift such cross-head to take up theslack of the brake-shoes. This rod 13 extends within the hollowpiston-rod 5 of the brake-cylinder, the inner end thereof be'ing inposition to be engaged by the piston-head, whereby such rod will beshifted simultaneously with the tubular piston-rod, so that to a certainextentit forms a part of the pistonrod, since it forms the connection orcoupling between such piston-rod and the cross-head.

A sleeve 15, having a squared opening 1G, iits on the squared portion1'7 of this rod 13 and within which the rod slides. In this organizationthis rod is shifted with the pistonhead to set the brakes; but on thereturn of this piston to its normal position by the action of the springthe weight of the brakeshoes returns the rod 13 to its normal position.This sleeve 15 is provided with a llanged end 15', by means of which itis held against longitudinal displacement in one direction within thehollow piston-rod 5 by a collar 19, secured on the interior of suchpiston-rod 5, and in the opposite direction by a centrally-bored cap 20,fastened to the end of said sleeve 15, and which cap abuts against thepawl-carrying ring hereinafter described and holds the same in properworking position. This sleeve 15 is rotatable within said pistonrod andis provided at one part thereof in one form shown with ratchet-teeth15", which are encircled by a ring 2l, carrying in the present instancea series of gravity pawls or dogs 22, each shown comprising a member 23,sliding in a slot or recess 2l of such ring 21 and having a series ofteeth. In place of these pawls thc ring may be provided with one or moreeccentrically-pivoted devices 25, effective to engage a smooth surface26 of the sleeve 15, thereby to rotate such sleeve.

Carried by the ring 21 is a projection, such as a roll 21', in positionto be engaged by the working faces of the actuator, and thereby rotatesaid ring 2l. From the foregoing it will be seen that when the ring ismoved in one direction the pawl ratchet-teeth will engage the teeth ofthe sleeve 15 and rotate the rod 13 within the piston-rod 5.

In the form shown in Fig. 2 the ratchet mechanism is substantiallysimilar to that just described. In this instance, however, theratchet-sleeve is bolted to the piston-rod. The piston-rod 5, however,is preferably provided with an enlarged threaded end 27, engaging theinterior threads of the cross-head member 7. In this form the piston-rodis connected with the piston-head by a coupling, which will permit therotation of such rod, while permitting longitudinal movement thereofwith the piston-head, and for this purpose the pistou-head is shownprovided with a projection 2S, to which by means of a bolt 29 is secureda tubular member or socketpiece 30, having a pair oftransversely-extending openings 3l, communicating with an annular groove33 on the end of the pistonrod which extends into said socket-piece.Through these openings 3l extend the bolts 32, which engage in suchannular groove 33, and while permitting the rod to rotate relatively tothe piston-head rigidly connect the two together for movementlongitudinally of the brake-cylinder. It will be obvious that thepiston-rod could project directly into the piston-head and be coupledthereto in the mannerjust described or in any other de sired way.

In each form shown herein the separation of the piston-rod from itscross-head is prevented by a ring 35, secured at the inner ends of thecross-head tubular member, whereby when the cross-head has been shiftedas far as the threads thereof will permitthe enlarged threaded end ofthe rod will engage this ring and prevent the separation of such parts.

In the organization shown in Fig. 3 the mechanism is substantiallysimilar to that shown in Fig. 1, except that the end of the rod 1S isprovided with a single enlarged or coarse thread 13,while the tubularcross-head member 12 is provided with similar threads, which, however,do not extend the full length thereof,whereby a space 40 is provided topermit the rod 13 to freely rotate within such cross-head member whenthe cross-head has been adj usted as far as its threads will permit.

In use it will be seen that when air is admitted to the brake-cylinderthe piston will be forced forward in the usual manner against the actionof its spring and push forward the cross-head,thereby operating thebrake-incohanism levers in the usual manner to set the brakes. Thisoperation of course carries the roll 21 along the straight surface a ofthe actuator-sleeve 8 until it reaches the forward curved surface c ofsuch sleeve, down which it will ride to the extent necessary to permitthe brake -shoes to effectively engage the wheels, this being permittedby the action of the ratchet mechanism, the teeth of the pawls IOO IIO

at this time sliding over the teeth of the sleeve 15. In order to insurethe setting of the brakes should the cam-path be of insufticent length,this cam-path is shown terminating in a longitudinally-extending portione, opening at the free end of the actuator, whereby when the rollreaches the endof the surface cit can move in the part c to the extentnecessary. The Walls e of this parte are shown as curved, thereby toproperly guide the rolls on the release of the brakes back into thecam-path. When the brake-shoes are released,the ratchet mechanism ofcourse prevents the return of the roll 2l toward the straight surface ctof the actuator, so that as the spring returns the piston-head and itsrod to their starting position the roll 21 passes directly across fromthe front curved surface e to the rear curved surface CZ of theactuator, whereupon the action of the spring forces it along such curvedsurface d to its starting-point. yAs the roll passes along this ,curvedsurface d the pawls of the ring rotate the ratchet-sleeve, which in turnrotates the rod to turn the same Within the crosshead and shift the samea distance corresponding to the length of the curved surface d, overwhich the spring has forced the roll, so that slack to an amount equalto the length of the curved surface d, over which the roll is forced,Will be taken up each time the brakes are released. By this improvedorganization it will be seen that each time the brake mechanism isreleased the brake-shoes are adjusted if any slack is presen t, andsince only an amount of slack equal to the length of the surface d canbe taken up each timeit follows that, however much slack may be presentowing to undue strain or otherwise upon the brake mechanism, suchmechanism Will not be adjusted to such an extent that when it returns toits normal condition it will refuse to properly Work. Furthermore, itwill be seen that in the organizations shown the ratchet mechanism willbe actuated each time the brake mechanism is released if any slack is tobe taken up. In Fig. l this ratchet mechanism is connected directly tothe tubular piston-rod, which is actuated or returned to its normalposition by its spring 6, so that whether the push-bar is returned toits normal position or not by the gravity of the brake-shoes slack Willnevertheless be taken' up, since this push-bar will in each instance berotated during the return of the tubular piston-rod. Moreover, byproviding the cam With independentl y-actin g faces c and dslack is nottaken up until after the mechanism is fully released from tension due tothe thrust of the piston-rod and the spring of the lever system, sincethe shifting of the cross-head is not effected until the roll has movedentirely across the space between the faces c and d and engaged vthelatter face CZ, at which time the brakeshoes and brake system arecompletely released, so that the taking up of slack is very muchfacilitated, While undue strain on the ratchet mechanism is avoided,

If, however, the roll of the ratchet mechanism returned over the face c,which Would be the case if such faces c and d were locatedin positionsoas to both engage the roll simultaneously, the taking up of slack Wouldnecessarily take place before the brake-shoes and brake mechanism'werecompletely released,

and consequently while such brake shoes were set, so' that a part ofthis adjustment would necessarily take place during a portion of thetime that such brake-shoes and brake mechanism Were set.

In the claims the term ratchet mechanism is intended to include theeccentricallyformed operating devices herein shown and described.

I claim as my inventionl. In a slack-adjuster, the combination, with acrossshead having an interiorly-threaded tubular part, of a pistonmember having a threaded part projecting into said tubular part; andmeans for rotating said piston member relatively to such cross-headthereby to take up slack of the mechanism.

2. In a slack-adjuster, the combination, with a cross-head having aninteriorly-threaded tubular part, of a piston member comprising apiston-rod rotatable independently of the piston-head and having athreaded part projecting into said tubular part; and means for rotatingsaid piston member relativelywto such cross-head thereby to take upslack of the mechanism. Y

. 3. In a slack-adjuster, the combination, with a cross-head having aninteriorly-threaded tubular part, of a piston member having `a threadedpart projecting into said tubular part; and means for rotating saidpiston member relatively to such cross-head thereby to take up slack ofthe mechanism, said means comprising an actuator havinga cam-path, andmeans in operative connection with said piston member and shifted bysaid actuator.

4. In a slack-adjuster, the combination,

with a cross-l1ead having an interiorly-threaded tubular part, of apiston member having,

a threaded part projecting into said tubular part; and means forrotating said piston member relatively to such cross-head thereby totake up slack of the mechanism, said means comprising an actuator havinga cam-path, and ratchet mechanism in operative connection With saidpiston member and shifted by said actuator.

5. An automatic slack-adjuster for` brake mechanism comprising, incombination with a brake-cylinder, a piston member rotatably connectedwith the cross-head of the lever mechanism; a cam-sleeve rigidly securedto said brake-cylinder and having cam-surfaces; ratchet mechanismcarried by said piston member and having a roll shifted by saidcamsurfaces and effective to rotate said piston member relatively tosaid cross-head thereby to shift the latter to take up slack.

6. An automatic slack-adjuster for brakes comprising, in combinationwith a brake- IOO IIO

cylinder, a device connected with the lever mechanism of the brakesystem and having an interiorly-threaded tubular sleeve; aspring-actuated piston member shiftable in said brake-cylinder andhaving a threaded end working in said threaded sleeve; an actuatorhaving a cam-path; a rotatable sleeve rigidly secured to said pistonmember; and means actuated by said actuator for rotating said sleeve andthereby the piston member to shift said lever-connected device.

7. An automatic slack-adjuster for brakes comprising, in combinationwith a brake-cylinder having a spring-actuated piston therein, a deviceconnected with the lever mechanism of the brake system and having aninteriorlythreaded tubular sleeve; a piston member connected with saidpiston and having a threaded end working in said threaded sleeve; anactuator having independentlyacting cam-surfaces; a rotatable sleeverigidly secured to said piston member; and ratchet mechanism operated byone of the cam-surfaces of said actuator for rot-ating said sleeve andthereby the piston member to shift the lever-connected device and takeup slack.

S. In a slack-adjuster, the combination, with a piston member and with amember connected therewith, and adapted to be adj usted longitudinallyrelatively thereto, of means for eifecting such adjustment, andcomprising an actuator having independently-acting cam-surfaces, oneeffective at one period and another at a dierent period; and meanscontrolled thereby for shifting said member.

9. In a slack-adjuster, the combination, with a piston member and with amemberconnected therewith, and adapted to be adjusted longitudinallyrelatively thereto, of means for effecting such adjustment, andcomprising an actuator having oppositely-located independently-actingcam-surfaces, one elective at one period and another at a differentperiod; and means controlled thereby for shifting said member- 10. In aslack-adjuster, the combination, with a piston member, and with a memberconnected therewith, and adapted to be adj usted longitudinallyrelatively thereto, of means for effecting such adjustment, andcomprising an actuator having independently-acting cam-surfaces, oneeffective at one period and another at a different period; a deviceconnected to one of said members and having a working surface; and meansin operative engagement with said working surface and provided with aprojection shifted by said camsurfaces at different periods to effectsuch adjustment and take up slack.

11. In combination, with a brake-cylinder, a piston member provided witha threaded surface; a member connected with the lever mechanism of thebrake system and having a threaded surface cooperating with the threadedsurface of said piston member whereby said piston member is rotatablerelatively to said lever-connected member to shift the latter, and meansoperative to rotate said piston member at a predetermined period therebyto shift said lever-connected member to take up slack, said meanscomprising an actuator having a pair of independently-actingcamsurfaces; a sleeve rigidly connected with said piston member; andmeans actuated by one of said cam-surfaces for rotating said sleeve andthereby the piston member.

12. In combination, with a piston member of a brake system and with amember connected with the lever mechanism of said brake system, suchmembers having rotatable connection, means for rotating one of saidmembers relatively to the other thereby to shift the other member andtake up slack, said means comprising an actuator having a pair ofindependently-acting cam-surfaces, and means actuated thereby and inoperative connection with the rotatable member.

13. In combination, with a brake-cylinder having a piston-head locatedtherein, a pistonrod rotatably connected with said pistonhead and havinga threaded surface; a member connected with the lever mechanism of thebrake system and also having a threaded surface cooperating with thethreaded surface of said piston-rod; and means for rotating saidpiston-rod thereby to shift the level'- connected member and take upslack.

14. In combination, with a brake-cylinder having a piston-head locatedtherein, a piston-rod rotatably connected with said pistonhead andhaving a threaded surface; a member connected with the lever mechanismof the brake system and also having a threaded surface cooperating withthe threaded surface of said piston-rod; and means for rotating saidpiston-rod thereby to shift the lever-connected member and take upslack, said means comprising an actuator having a cam-surface; a devicerigid with said piston-rod and means shifted by said cam-surface forrotating said device and thereby the piston-rod.

15. In combination, with a brake-cylinder having a piston-head locatedtherein, a pistonrod rotatably connected with said piston-head andhaving a threaded surface; a member connected with the lever mechanismof the brake system and also having a threaded surface coperating withthe threaded surface of said piston-rod; means for rotating saidpiston-rod thereby to shift the lever-connected member and take upslack, said means comprising a sleeve rigidly connected to saidbrake-cylinder and having a pair of cam-surfaces; a sleeve rigidlyconnected to said piston-rod and having a ratchet-surface; a pawl inengagement With said ratchet-surface; and a projection shifted by saidcam-surface for actuating said pawl.

1G. In combination, with a piston member of a brake mechanism, a memberconnected with the lever mechanism of said brake mechanism, one of saidmembers having a plurality of threads and the other of said members IOOIIO

having one or more threads, and one of said members being rotatablerelatively to the other, said member having the plurality of threadsalso having a space whereby the rotatable member may be rotated at apredetermined period-Without shifting the other of said members; andmeans for rotating said rotatable member thereby to take u p slack ofthe brake mechanism.

17. In combination, with a piston member of a brake mechanism, a memberconnected with the lever mechanism of said brake meehanism, one of saidmembers having a plurality of threads and the other of said membershaving one ormore threads, and one of said members being rotatablerelatively to the other, said memberhaving the plurality of threads alsohaving a space whereby the rotatable member may be rotated at apredetermined period Without shifting the other of said members, andmeans for rotating said rotatable member thereby to take up slack of thebrake mechanism, said means comprising an actuator having acam-surface,and ratchet mechanism operated by said cam-surface to rotate saidrotatable member.

I8. In combination, with a spring-actuated rotatable piston member of abrake mechanism, said member having one or more threads, a memberconnected With the lever mechanism of the brake mechanism andhaving aninternally-threaded sleeve With a space at one part thereof whereby thepiston member is free to rotate at a predetermined period Withoutshifting said internally-threaded member, and means for rotating saidpiston member thereby to shift said internally-threaded member to takeup slack of the brake mechanism.

19. In a slack-adjuster, the combination,

with a piston member,and with a member connected with the lever system,such members having a rotatable connection, of a cam-sleeve rigidilysecured in position and having a camsurface; mechanism having a deviceshifted by said cam-surface and effective to rotate said piston memberrelatively to said leverconnected member thereby to take up slack.

'20. In a slack-adjuster, the combination, with a spring-actuatedtubular piston-rod, of a piston member longitudinally shiftable therein;lever mechanism adj ustably connected to said piston member; meanssecured to, and movable With, said tubular piston-rod ing the return ofsaid piston-rod under the action of its spring to its normal position;and an actuator for said means.v

21. In a slack-adjuster, the combination, with a spring-actuated tubularpiston-rod, of a piston member longitudinally shiftable therein; levermechanism adjnstably connected to said piston member; ratchet mechanismsecured to, and movable with, said tubular piston-rod and eifective torotate said piston member thereby to adjust the lever mechanism duringthe return of said pistonrod under the action of its spring to itsnormal position; and an actuator for said ratchet mechanism.

22. In a slack-adjuster, the combination, with a spring-actuated tubularpiston-rod, of a piston member longitudinally shiftable therein; levermechanism adjustably connected to said piston member; ratchet mechanismsecured to, and movable with, said tu` bular piston-rod and efective torotate said piston member thereby to adjust the lever mechanism duringthe return of said pistonrod under the action of its spring to itsnormal position; and an actuator having a cams surface for said ratchetmechanism.

23. In a slack-adjuster, the combination, With a spring-actuated tubularpiston-Tod,- of ratchet mechanism secured to and movable therewith; apiston member rotatable with said ratchet mechanism and having a slidingadjustment relatively thereto; a member rotatively connected with saidpiston member and having connection with lever mechanism; and anactuator for operating said ratchet mechanism, whereby during the returnYof such tubular piston-rod to its normal position under the action ot'its spring, such piston member Will be rotated thereby to take up slack.

24. In an automatic slack-adj uster for brake mechanism, thecombination, With a brakecylinder, of piston mechanism; means connected,through the instrumentality of a ro-V tary member with said pistonmechanism for independent movement and with the lever mechanism of saidbrake mechanism; an actuator-sleeve secured to said brake-cylinder andhaving a transversely-extending campath terminating in alongitudinally-extending portion opening at the vfree end of saidsleeve; a device shiftable in said path and effective, through theinstrumentality of ratchet mechanism to rotate said rotatable member onthe release of the brake to there; by shift said lever-connected meansand take up slack.

SINCLAIR J. JOHNSON. Witnesses:

FRED. J. DoLn, C. E. Voss.

IOO

